Synchronizing with OS X

To use ownCloud with iCal you will need to use the following URL:

https://example.com/remote.php/dav/principals/users/USERNAME/

The setup is basically the same as with iOS using the path
https://example.com/remote.php/dav/principals/users/USERNAME/ to sync
with ownCloud. For OS X 10.7 Lion and 10.8 Mountain Lion everything
works fine, but OS X 10.6 (Snow Leopard) and older needs some fiddling
to work. A user contributed the following:

Make sure, addressbook is not running. If it is, select the windows and press Command+Q to terminate it.

Navigate to UsersYOUR_USERNAMELibraryApplication SupportAddressBookSources.
If you already have some kind of addressbook setup, it is likely you
will see some folders named like this
BEA92826-FBF3-4E53-B5C6-ED7C2B454430. Note down what folders there are
now and leave the window open.

Open addressbook and try to add a new CardDav addressbook. At this point, it does not matter
what information you enter. It will come up with the same error message you mentioned
before when you click Create. Ignore it and click Create again.
A non-functional addressbook will be added.

Close addressbook again using Command+Q

Go back to the folder window from step 2. You will now see a newly created folder with another
long string as its name.

Navigate to the newly created folder and edit the Configuration.plist
with your favorite text editor.